The Ur-Roadster (which is German for “original roadster”) was created in 1990, so just one year after the launch of the Z1 - yes, that weird roadster with the doors that slide downwards. However, in terms of looks, the Ur-Roadster shows more resemblance to the BMW Z3, which launched five years later. And judging by the aforementioned side view details, it is safe to say that the Ur-Roadster has a similar, if not the same, setup.
But there’s one more key information we need to know to understand this car: The powertrain. Because under that weird-looking bonnet, we will not find the 170 hp engine used in the Z1, but rather the 2.3-liter inline-four from the E30 M3, producing 220 hp. This also explains why the Ur-Roadster was often referred to as “Z1 M”…
Overall, the Ur-Roadster was a concept car that grew out of the BMW Z1, with the idea behind it being the creation of an entry-level M car. Despite never being released, it still influenced the Z3 heavily, and with the release of the Z3 M, the “cheap” M car finally became a reality. Today, the fully working, drivable concept spends its time in a big underground car park in the north of Munich, along with tons of other BMW concepts, race cars, and low-mileage production vehicles - a couple of which you’ll surely see in this series at some point!
Sources: CarThrottle; OldConceptCars